Hetzner is offering new servers with SSD, good news for people who want to run ZFS (for ZIL and/or L2ARC). See the EX server configuration list for more information [1]. Unfortunately they don’t specify what brand of SSD, this is a concern for me as some of the reports about SSD haven’t been that positive, getting whichever SSD is cheapest isn’t appealing. A cheap SSD might be OK for L2ARC (read cache), but for ZIL (write cache) reliability is fairly important. If anyone has access to a Hetzner server with SSD then please paste the relevant output of lsscsi into a comment.

The next issue is that they only officially offer it on the new “EX 8S” server. SSD will be of most interest to people who also want lots of RAM (the zfsonlinux.org code has given me kernel panics when running with a mere 4G of RAM – even when I did the recommended tuning to reduce ARC size). Also people who want more capable storage options will tend to want more RAM if only for disk caching.

But I’m sure that there are plenty of people who would be happy to have SSD on a smaller and cheaper server. The biggest SSD offering of 240G is bigger than a lot of servers. I run a Hetzner server that has only 183G of disk space in use (and another 200G of backups). If the backups were on another site then the server in question could have just a RAID-1 of SSD for all it’s storage. In this case it wouldn’t be worth doing as the server doesn’t have much disk IO load, but it would be nice to have the option – the exact same server plus some more IO load would make SSD the ideal choice.

The biggest problem is that the EX 8S server is really expensive. Hard drives which are included in the base price for cheaper options are now expensive additions. A server with 2*3TB disks and 2*240G SSD is E167 per month! That’s more expensive than three smaller servers that have 2*3TB disks! The good news for someone who wants SSD is that the Hetzner server “auction” has some better deals [2]. As is always the case with auction sites the exact offers will change by the moment, but currently they offer a server with 2*120G SSD and 24G of RAM for E88 per month and a server with 2*120G SSD, 2*1.5T HDD, and 24G of RAM for E118. E88 is a great deal if your storage fits in 240G and E118 could be pretty good if you only have 1.5T of data that needs ZFS features.

The main SSD offering is still a good option for some cases. A project that I did a couple of years ago would probably have worked really well on a E167/month server with 2*3TB and 2*240G SSD. It was designed around multiple database servers sharding the load which was largely writes, so SSD would have allowed a significant reduction in the number of servers.

They also don’t offer SSD on their “storage servers” which is a significant omission. I presume that they will fix that soon enough. 13 disks and 2 SSD will often be more useful than 15 disks. That’s assuming the SSD doesn’t suck of course.

The reason this is newsworthy is that most hosted server offerings have very poor disk IO and no good options for expanding it. For servers that you host yourself it’s not too difficult to buy extra trays of disks or even a single rack-mount server that has any number of internal disks in the range 2 to 24 and any choice as to how you populate them. But with rented servers it’s typically 2 disks with no options to add SSD or other performance enhancements and no possibility of connecting a SAN. As an aside it would still be nice if someone ran a data center that supported NetApp devices and gave the option of connecting an arbitrary number of servers to a NetApp Filer (or a redundant pair of Filers). If anyone knows of a hosting company that provides options for good disk IO which are better than just providing SSD or cheaper than E167 per month then please provide the URL in a comment.